Related papers: MeerKAT discovery of a high-redshift strongly-lens…
Two recent discoveries have made it possible for us to begin using high-z quasars as standard candles to construct a Hubble Diagram (HD) at z > 6. These are (1) the recognition from reverberation mapping that a relationship exists between…
OH megamasers (OHMs) emit primarily in the main lines at 1667 and 1665 MHz, and differ from their Galactic counterparts due to their immense luminosities, large linewidths and 1667/1665 MHz flux ratios, which are always greater than one. We…
The detection of high-redshift ($z>$3) blazars enables the study of the evolution of the most luminous relativistic jets over cosmic time. More importantly, high-redshift blazars tend to host massive black holes and can be used to constrain…
We search for strongly lensed and multiply imaged gravitational wave signals in the second observing run of Advanced LIGO and Advanced Virgo (O2). We exploit a new source of information, the so-called Morse phase, which further mitigates…
The hydroxyl radical (OH) is found in various environments within the interstellar medium (ISM) of the Milky Way and external galaxies, mostly either in diffuse interstellar clouds or in the warm, dense environments of newly formed low-mass…
Dark Matter (DM) halos with masses below $\sim10^{8}$ $M_{\odot}$, which would help to discriminate between DM models, may be detected through their gravitational effect on distant sources. The same applies to primordial black holes,…
In this paper we present follow-up optical observations of Ultra Steep Spectrum sources that were found by matching 150 MHz GMRT sources with either the 74 MHz VLSS or the 1400 MHz NVSS. These sources are possibly high-redshift radio…
We report the discovery of two remarkable high-opacity HI 21cm absorbers against low-luminosity active galactic nuclei (AGNs), at $z = 1.2166$ towards J0229+0044 and at $z=1.1630$ towards J0229+0053. The absorbers were detected in an…
Context: The Red MSX Source (RMS) survey has identified a large sample of candidate massive young stellar objects (MYSOs) and ultra compact (UC) HII regions from a sample of ~2000 MSX and 2MASS colour selected sources. Aims: To search for…
We used Arecibo Observatory and the Green Bank Telescope to observe OH in twelve early-type galaxies with known reservoirs of dense gas. We present three new detections of OH in absorption in the 1667 MHz line. One objective of our survey…
We report the discovery of two new giant radio galaxies (GRGs) using the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey. Both GRGs were found within a 1 deg^2 region inside the COSMOS field. They have redshifts…
We present results from our search for HI 21-cm and OH 18-cm absorption at z~1-1.4 towards red quasars showing strong MgII absorption using uGMRT. The quasars J1501+1822 and J1521+5508 show multiple strong associated MgII absorption at…
Using an ultra-deep blind survey with the MUSE integral field spectrograph on the ESO Very Large Telescope, we obtain spectroscopic redshifts to a depth never explored before: galaxies with observed magnitudes m > 30 - 32. Specifically, we…
The MeerKAT Absorption Line Survey (MALS) has observed 391 telescope pointings at L-band (900 - 1670 MHz) at $\delta\lesssim$ $+20\deg$. We present radio continuum images and a catalog of 495,325 (240,321) radio sources detected at a…
The James Webb Space Telescope (JWST) has discovered a surprising abundance of bright galaxy candidates in the very early Universe ($< 500$ Myrs after the Big Bang), calling into question current galaxy formation models. Spectroscopy is…
We present the confusion-limited 1.28 GHz MeerKAT DEEP2 image covering one $\approx 68'$ FWHM primary beam area with $7.6''$ FWHM resolution and $0.55 \pm 0.01$ $\mu$Jy/beam rms noise. Its J2000 center position $\alpha=04^h 13^m 26.4^s$,…
We report the discovery of a unique object in the MeerKAT Galaxy Cluster Legacy Survey (MGCLS) using the machine learning anomaly detection framework Astronomaly. This strange, ring-like source is 30' from the MGCLS field centred on Abell…
With bolometric luminosities exceeding $10^{48}$ erg s$^{-1}$, powerful jets and supermassive black holes at their center, MeV blazars are some of the most extreme sources in the Universe. Recently, the Fermi-Large Area Telescope detected…
We report the discovery of an unambiguous, substantial low-energy cutoff in the broad band X-ray spectrum of the radio quasar RXJ1028.6-0844 at a redshift of 4.276 obtained with the ASCA satellite, which we preferably explained as…
We report the identification from multi-wavelength observations of the Fermi Large Area Telescope (LAT) source 4FGL J1405.1-6119 (= 3FGL J1405.4-6119) as a high-mass gamma-ray binary. Observations with the LAT show that gamma-ray emission…